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function is not described

WP_Theme::scandir() WP 3.4.0

Scans a directory for files of a certain extension.

This is a method of the class: WP_Theme

Hooks from the method
Return

Array/false. Array of files, keyed by the path to the file relative to the $path directory prepended with $relative_path, with the values being absolute paths. False otherwise.

Usage

$var = WP_Theme::scandir( $path, $extensions, $depth, $relative_path );
$path(string) (required)
Absolute path to search.
$extensions(array/string/null)
Array of extensions to find, string of a single extension, or null for all extensions.
Default: null
$depth(int)
How many levels deep to search for files. Accepts 0, 1+, or
-1 (infinite depth).
Default: 0
$relative_path(string)
The basename of the absolute path. Used to control the returned path for the found files, particularly when this function recurses to lower depths.
Default: ''

Changelog

Since 3.4.0 Introduced.

Code of WP Theme::scandir: wp-includes/class-wp-theme.php WP 5.2.2

<?php
private static function scandir( $path, $extensions = null, $depth = 0, $relative_path = '' ) {
	if ( ! is_dir( $path ) ) {
		return false;
	}

	if ( $extensions ) {
		$extensions  = (array) $extensions;
		$_extensions = implode( '|', $extensions );
	}

	$relative_path = trailingslashit( $relative_path );
	if ( '/' == $relative_path ) {
		$relative_path = '';
	}

	$results = scandir( $path );
	$files   = array();

	/**
	 * Filters the array of excluded directories and files while scanning theme folder.
	 *
	 * @since 4.7.4
	 *
	 * @param string[] $exclusions Array of excluded directories and files.
	 */
	$exclusions = (array) apply_filters( 'theme_scandir_exclusions', array( 'CVS', 'node_modules', 'vendor', 'bower_components' ) );

	foreach ( $results as $result ) {
		if ( '.' == $result[0] || in_array( $result, $exclusions, true ) ) {
			continue;
		}
		if ( is_dir( $path . '/' . $result ) ) {
			if ( ! $depth ) {
				continue;
			}
			$found = self::scandir( $path . '/' . $result, $extensions, $depth - 1, $relative_path . $result );
			$files = array_merge_recursive( $files, $found );
		} elseif ( ! $extensions || preg_match( '~\.(' . $_extensions . ')$~', $result ) ) {
			$files[ $relative_path . $result ] = $path . '/' . $result;
		}
	}

	return $files;
}